Can I have a COVID-19 vaccination before a CT scan?

It is important to advise your oncologist or radiographer if you have received the COVID-19 vaccine recently. This is because the vaccine can cause the lymph nodes in your armpit and neck to swell which can be detected by CT scans used to diagnose and monitor cancers.

This is particularly detected by FDG PET/CT scans, in which you are given a contrast medium containing a type of radioactive sugar that is taken up by active cells. When an immune response to a vaccine takes place, the cells in the lymph nodes near the injection site become very active and take up a lot of this sugar. Depending on the type of cancer, you may be able to request the injection on the opposite side to your tumour. If possible, have the vaccination at least 2 weeks before a scheduled scan or as soon as you can afterwards. Do not delay any treatment.

What is the priority - an influenza vaccine or a COVID-19 vaccine?

The COVID-19 mRNA vaccine two-dose schedule should take priority over influenza (flu) vaccine.

The flu vaccine can be administered two weeks after the second dose of COVID-19 vaccine, which is given at least 21 days after the first dose. 

How should we space MMR, influenza and COVID-19 vaccination?

Please continue to allow a four-week gap when giving the MMR vaccine before the COVID-19 vaccine where possible. However, the gap can be reduced to two weeks when giving the MMR vaccine after the second dose of the COVID-19 vaccine. Complete both doses of the COVID-19 vaccine, 21 days apart, before giving another vaccine.

Please continue to allow a two-week gap between the COVID-19 vaccine and influenza vaccine where possible, regardless of the order they’re given.

Having a gap between the different types of vaccinations makes it easier to judge which vaccine may be responsible for any side effects. Note that there are no clinical safety concerns should the gap between vaccines be less than the recommendations above. Do not delay vaccination if such a gap is not possible.

The MMR and influenza vaccines can be given at the same time.

The Ministry of Health has put together a flowchart for healthcare providers managing MMR and influenza vaccinations around COVID-19.

Can other vaccines be administered with a COVID-19 vaccine?

Currently Medsafe advice is only available for the mRNA vaccine from Pfizer/BioNTech (Comirnaty™) vaccine.

A two-week gap is generally recommended after any non-live vaccine, including influenza, and the Comirnaty mRNA COVID-19 vaccine. If a live vaccine, such as MMR, varicella and zoster vaccine has been given, then a four-week gap is generally recommended before Comirnaty. If Comirnaty, is given first, then maintain a two week gap before any other vaccines. Do not delay if a gap between these vaccines is not practicable.

Please note that two doses of the mRNA vaccine are required, given at least 21-days apart. These recommendations are continually being reviewed.

Will booster doses of a COVID-19 vaccine be needed?

Not enough time has passed since first vaccinations were given to be able to answer this question.

People enrolled in clinical trials are being followed up closely, which will allow this question to be answered in due course. For more information, please click here.

It is expected that small adjustments may be made to the vaccine if the COVID-19 virus changes so much that vaccine loses effectiveness. In this case booster doses will be required to better match the virus variants in circulation, like for the influenza vaccine. How frequently these changes will need to be made is unknown. A major advantage of mRNA vaccine technology is that these changes can be made very quickly (new batches available within a few months compared with more than 6 months for seasonal flu vaccines).

What is the acceptable timeframe between the first and second doses of the Comirnaty vaccine?

To be fully immunised with Comirnaty requires two doses given at least 21 days apart.

Vaccinators are advised not to give the second dose earlier than this, and while longer spacing is acceptable, the recommended spacing is for the second dose to be given as close after 21 days as possible.

What is the guidance around receiving a COVID-19 vaccine and having a general anaesthetic?

Based on first principles and our experience with other vaccines, there is no expectation that an anaesthetic would affect the safety or immunogenicity of the mRNA COVID-19 vaccine.

The general recommendation when planning vaccination with any vaccine is explained in Section 3.1.3 in the Immunisation Handbook 2020

If more than one vaccine becomes available, could taking two different vaccines boost the effectiveness?

We do not know the answer to this yet as it is still being investigated in clinical trials. Currently, the COVID-19 vaccines are not interchangeable.

There is no data available on the interchangeability between COVID‑19 vaccines, such that, where possible other vaccines should not be substituted to complete the course. So far, the only COVID-19 vaccine available for use in New Zealand is Comirnaty (Pfizer/BioNTech). Other vaccines are undergoing the Medsafe approval process.

To be fully immunised with Comirnaty, two doses are required, to be given at least 21 days apart. There is no maximum duration between doses, so it is not necessary to restart the course or give a third dose if it has been longer than 21 days since dose one.

For more information, please click here.

Who can administer COVID-19 vaccines in New Zealand and how are they trained?

Staff administering COVID-19 vaccines must be authorised vaccinators or qualified medical staff.

The criteria for nurses to become authorised vaccinators is set out in appendix 4 of the Immunisation Handbook. Training for administering the COVID-19 vaccines is in addition to this criteria, therefore all vaccinators are already qualified and experienced. 

Training for the first cohort of vaccinators administering the Pfizer/BioNTech vaccine takes the form of online learning and webinars. This training includes detailed disease and vaccine-specific information, vaccination process information, paperwork and record-keeping, vaccine research and a review of the positive safety profile for this vaccine. They also cover responding to common concerns and where staff can go to access further support and clinical advice. This is followed by additional webinars to ask further questions and a clinical support line for vaccinators. Training will continue to expand and support more vaccinators to become authorised and complete the COVID course.  

What is the process New Zealand vaccinators are following to administer COVID-19 vaccines?

Vaccinators are following normal best practice in drawing up and administering the Pfizer/BioNTech vaccine. This is consistent with standard immunisation guidelines.

Some nurses are finding they can sometimes get up to six doses out of the vial, consistent with information from the vaccine manufacturer.

COVID-19 vaccines in pregnancy and breastfeeding

Pregnant people are encouraged to be vaccinated against COVID-19 at any stage of pregnancy.

In pregnancy, the risk of severe COVID-19 complications is much higher than in people who are not pregnant. The updated recommendation aligns with recommendations in other countries and is based on international evidence from a large number of people who have already received mRNA COVID vaccines when pregnant and no additional safety concerns have been shown. There is also increasing evidence that antibodies made by the mother after vaccination are shared with the baby in the cord blood that are likely to also protect her newborn baby against COVID-19.

As with all vaccines on the New Zealand Immunisation Schedule, there are no safety concerns about giving mRNA COVID-19 vaccine to women who are breastfeeding and by being vaccinated, mothers can provide some protection against COVID-19 for their babies in breastmilk.

Please refer to the Immunisation Advisory Centre's COVID-19 vaccination in pregnancy fact sheet for more information.

Reference

Shimabukuro TT, Kim SY, Myers TR, et al. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons. N Engl J Med. 2021 DOI: 10.1056/NEJMoa21049